Curious if others have had this experience too - many successful founder CEOs I've known through my career (working closely with them) are excellent at ball-par

Curious if others have had this experience too - many successful founder CEOs I've known through my career (working closely with them) are excellent at ball-parking / order-of-magnitude / back-of-napkin thinking off the top of their mind. There's something about it that IMO is an excellent 'tell' for a certain kind of intelligence especially for startups. I imagine part of it is that it's a good sign of 'technical skills' like fluency with math, and fluency with modelling scenarios. The other part is it's a 'demonstration of fitness' to others. Like, wow, our CEO is SMART and thinks FAST - great!